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584. GEOMOS: Semi-Empirical SCF System for Dealing
with Solvent Effects and Solid Surface Adsorption and
GMHELP: Program to Create Input Files for GEOMOS
by (GEOMOS) D. Rinaldi, P. E. Hoggan and A. Cartier and (GHELP) A. Cartier, Laboratoire de Chimie ThO(e,+)orique (U.A.C.N.R.S.no.510), UniversitO(e,+) de Nancy I, Domaine Universitaire Victor-Grignard, B.P. 239, 54506 Vandoeuvre-les Nancy Cedex, France GEOMOS The purpose of this program is the simultaneous determination of the relative position of the atoms in a molecule corresponding to a minimum of energy and the molecular orbitals (for open and closed shells) using a Slater AO basis and the CNDO, INDO, MINDO, MNDO or AM1 assumptions. It can be used for the elements with atomic numbers from 1 (hydrogen) to 54 (xenon). The optimization of the molecular geometry uses the procedure proposed by Davidon and modified by A. Murtagh and A. Fletcher. Variations of total energy with the atomic coordinates of the molecule are calculated analytically from the derivatives of the two-center integrals occurring in the semi-empirical SCF methods. In addition, it allows the simulation of a solvent effect as well as the computation of a large number of physicochemical properties of the ground and excited states. GMHELP The purpose of this program is the creation of a data file containing all the information needed by GEOMOS, i.e., semi-empiricalmethod used, geometry optimization, physical properties computed, bases of atomic orbitals, solvent effect, interaction with a planar surface, as well as initial coordinates of the atoms. For each question, GMHELP gives a set of possible answers and guides the choice of any user who can type "?". The compatibility between the semi-empirical method used and the physical properties requested is tested, and the user can change his requirements at any state of the "conversation" to take the program's recommendations into account. Concerning the geometric data, values which seem obvious are highlighted, and the user can change them then. Data are entered unformatted, and GMHELP puts them in the appropriate format for GEOMOS. FORTRAN 77 (IBM 6150) Lines of Code: 53,520 |